The term “haptic” interface commonly designates any man-machine interface that allows force feedback and/or tactile feedback for the user.
The haptic interfaces that can be manipulated with a single hand can be classified into two fundamentally different categories. The first category includes the “ground-based>> haptic interfaces. In the present text, <<ground-based>> haptic interface designates any haptic interface that generally comprises a structure that is placed on a surface (floor, desk, table, etc.) and that is designed to be manipulated with a single hand. The second category includes the so-called “man-based” interfaces, which are constituted by portable devices designed to be attached to the user. The most common examples of <<man-based>> interfaces are constituted by haptic devices that are attached to one hand, such as force feedback gloves or the haptic devices described, for example, in the publications WO-A-0207143 and WO-A-9851451.
The invention belongs to the field of the haptic interfaces in the first category mentioned above, i.e. “ground based.”
In this field, a first example of a known “ground-based” haptic interface is described in the U.S. Pat. No. 6,417,638. This interface is a haptic device with six degrees of freedom (only three of which are motorized) and essentially includes an arm articulated in relation to a fixed base and manipulable by a single hand. This type of haptic device has a very sophisticated design and is therefore very expensive to produce; moreover, this haptic device is bulky and is generally used with the forearm in the air, which makes using the device tiring from a muscular point of view.
A second example of a known “ground-based” haptic interface is described in particular in international patent application WO-A-9628777. The interface described in this publication is used as a 3D computer peripheral and includes a single tactile-feedback actuator that can be manipulated with the fingertips. More particularly, this single actuator is in the form of a ball that can be manipulated by a user. The ball's rotation on itself allows control on two axes X and Y, while control on a third axis Z transverse to the plane (X,Y) is obtained by a vertical translational movement of the ball. Advantageously, this type of <<ground-based>> interface with a single actuator manipulable by the fingertips is not very bulky and can be used with the hand resting at least partially on a surface, which makes it less tiring to use from a muscular point of view, compared to the example of “ground-based” interfaces of the type described in the aforementioned patent U.S. Pat. No. 6,417,638.